It's a bit of a pain, but can you definitely go on a diet? I bought a container called "Tanita Shokudo Recommended Range Compatible Storage Container".
A container mainly for holding rice (white rice). A set of 2 sizes that can hold about 140g (4.94oz) and 2 sizes that can hold about 100g (3.53oz). "Rice 140g (4.94oz) (235kcal)" is the amount equivalent to a normal serving for eating out, and "Rice 100g (3.53oz) (168kcal)" is the amount recommended by Tanita, which is known for its healthcare business. Although 100g (3.53oz) of rice seems to be less for the female writer, it is calculated that reducing the amount of rice by 40g (1.41oz) can reduce calories by about 70kcal. If you continue every day, you may get a visible change in half a year or a year.
In addition, "Tanita Shokudo Recommended Range Compatible Storage Container" has other features such as "Since the lid is pushed up by the power of steam, it can be put in the microwave as it is without removing the lid" and "It can be stored compactly". How about using it as a storage container or a lunch box container instead of a kitchen scale? It is sold on various mail order sites and the price range is around 400 yen.